Walking with the entire sole of the foot on the ground, as humans, bears, raccoons, and rabbits do.
[French : Latin planta, sole of the foot; see plat- in the Appendix of Indo-European roots + Latin -gradus, going (from gradī, to walk, go; see ghredh- in the Appendix of Indo-European roots).]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.